Material such as audio/video material, data and software programs may be produced for variety of different applications. One of the fields of greatest demand for audio/video material is in the entertainment field where an increase in the number of television channels, particularly in Europe has fuelled an increase in the demand for audio/video productions.
Today, a business profile of the production and consumption of material is characterised by a growing number of independent production companies, which both generate material and have a demand for material to produce for example, audio/video productions. The management and distribution of material, to many interested parties whether or not for commercial reasons, therefore represents a technical problem.
In co-pending International patent application number PCT/GB01/01493 (I-00-74) there is disclosed a multimedia transaction processor for facilitating the sale of multimedia material. A multimedia transaction processor includes a media server operable to store multimedia material from a seller client, and to store metadata representing the content of the multimedia material and data identifying the seller providing the multimedia material. The metadata and the identifying data are stored in association with the multimedia material. An access processor is operable to retrieve from the server possible multimedia material content items corresponding to requested multimedia content by generating meta data from the data requesting the multimedia content. The generated meta data is compared with the meta data stored in association with the multimedia material, and from the comparison possible multimedia content items are retrieved from the server. Data representative of the possible multimedia content items are communicated to a buying client processor. A transaction controller is operable, in response to selection data, to communicate data requesting the selected multimedia content items to the seller client identified by the stored identification and to complete the transaction with the buyer. The multimedia transaction processor provides a facility for clients to sell and to buy multimedia material in order to fulfil a particular need.
GB-B-2329547 (Aliroo Ltd) discloses a system which security tags digital media, by for example scarring and descarring an image. The scarring process is carried out by a user who would typically be one responsible for protecting the rights of the rights owner in the image. The user selects an encryption key and one or more encryption modes, which include:                Shuffling pixels in a group of pixels;        Shuffling groups of pixels;        Modifying colour values within a pixel.        
Also a scar area is selected.
A potential licensee opens a scarred image. If the licensee wants the image he pays a fee and receives a licensing password. The licensee employs a descarring tool, and uses it to extract a descarring key and a transaction identifier from the password. The scar is removed and the transaction identifier embedded as an invisible label in the image. This is done in a way which prevents the licensee tampering with the process. The transaction identifier identifies the licensee.